What’s the first thing over 100 million Americans do when they wake up? If you’re one of the many java-addicted consumers, you probably make a beeline for the coffee brewer and with your eyes half-open, brew up a fresh cup of the aromatic brown elixir. Now despite the rumors that have circulated from Boston to Beijing, coffee is actually a healthy beverage that is consumed by billions around the world. Certainly, if you take a common-sense approach to whether coffee is safe (or not), it would be perverse to withhold the provisional assent that it is indeed safe considering that billions of individuals drink it every day.
Furthermore, the key ingredient in coffee, caffeine is actually an amazing substance that has a wide variety of functions. For instance, caffeine improves performance and endurance during prolonged, exhaustive exercise. But it also promotes gains in short-term, high-intensity athletic performance. Caffeine decreases your perception of pain during exercise. This might explain why fitness competitors routinely down a cup of java right before exercise. Caffeine also improves mental alertness and reduces your perception of fatigue. Moreover, habitual intake does decrease caffeine’s ergogenic properties.
Coffee – the amazing elixir
And you might be surprised to hear that coffee itself may be a health food. For instance, we know that regular consumption of coffee decreases the risk of type II diabetes. A recent study examined the long-term relationship between coffee consumption and other caffeinated beverages and incidence of type 2 diabetes mellitus: The Nurses’ Health Study and Health Professionals Follow-up Study.
Scientists tracked 41,934 men from 1986 to 1998 and 84,276 women from 1980 to 1998. These were free of diabetes, cancer, or cardiovascular disease at baseline. Coffee consumption was assessed every 2 to 4 years through validated questionnaires. What did they find?
These investigators documented 1333 new cases of type 2 diabetes in men and 4085 new cases in women. The authors found an inverse association between coffee intake and type 2 diabetes after adjustment for age, body mass index, and other risk factors. In other words, those who drank the most coffee tended to have the least risk of diabetes. Even more intriguing, total caffeine intake from coffee and other sources was associated with a statistically significantly lower risk for diabetes in both men and women; meaning that decaffeinated coffee may not be as good for you as the caffeine-filled. The author’s concluded that the “data suggest that long-term coffee consumption is associated with a statistically significantly lower risk for type 2 diabetes.”(1)
The Amazing Trio – Energy, Performance Enhancement, and Fat Burning
Energy
Perhaps the most common reason for ingesting caffeine or caffeine-containing beverages is the pick-me-up effect. For instance, one study examined one hundred and forty-four volunteers (72 male, 72 female, mean age 21 years) and had them consume breakfast (cereal versus no breakfast) and caffeine (caffeinated versus decaffeinated coffee). They found that those who consumed breakfast cereal had a more positive mood at the start of the test sessions, performed better on a spatial memory task, and felt calmer at the end of the test session than those in the no breakfast condition (lesson: don’t skip breakfast:)). Consuming caffeine improved the “encoding of new information and counteracted the fatigue that developed over the test session.”(2)
Performance Enhancer
Caffeine is the most versatile and effective ergogenic aid (i.e. something that enhances exercise performance). A prominent exercise physiologist, David Costill, Ph.D., performed the ground-breaking study on caffeine and exercise 26 years ago! He took nine competitive cyclists (two females and seven males) and had them bike until exhaustion at 80% of V02 max. (Note: V02 max, also known as maximal oxygen uptake, is a measure of how well your cardiopulmonary system functions).
Each subject consumed coffee containing 330 mg of caffeine 60 min before the exercise or a placebo (decaffeinated coffee). Following the ingestion of caffeine, the subjects were able to perform an average of 90 minutes of cycling as compared to an average of 76 minutes in the placebo trial. This reflects an 18% increase! They also found that subjects burned more fat (aka lipolysis) as shown by measurements of plasma-free fatty acids, glycerol, and respiratory exchange ratios. In fact, fat oxidation or burning was significantly higher (107% greater) during the caffeine trial (118 g or 1.31 g/min) than in the placebo trial (57 g or 0.75 g/min). Also, the perception of effort was much less in subjects after consuming subjects indicating that exercise felt easier.(3)
Other research has confirmed the performance-enhancing effects of caffeine.(4-7)
Thermogenesis
A recent study looked at energy expenditure, fat oxidation or burning, and norepinephrine (NE) kinetics (i.e. how ‘adrenaline-like hormones are metabolized) after caffeine or placebo ingestion using placebo-controlled double-blind conditions. The dose administered was 5 mg of caffeine per kilogram of fat-free mass (which is mainly muscle and bone). Translation: For the young men, they consumed about 350 mg while the old men consumed about 295 mg. (Therefore, the young men had more FFM than the old men).
They studied 10 older (65-80 yr) and 10 younger (19-26 yr) men who were moderate consumers of caffeine. Caffeine ingestion resulted in similar increases in both the old and young men for plasma caffeine levels; thus both young and old absorb caffeine equally well. Metabolic rate or energy expenditure increased similarly by 11% in young and 9.5% in the older men. According to the scientists, “older and younger men show a similar thermogenic response to caffeine ingestion, whereas older men show a smaller increase in fatty acid availability after a caffeine challenge. These metabolic differences are not related to alterations in norepinephrine kinetics or fat oxidation.” (8) A recent study presented at the International Society of Sports Nutrition Conference in Las Vegas showed that a functional coffee beverage that also contained bitter orange, hydroxycitric acid, and chromium produced a significant increase (up to 30%) in metabolic rate. (9) This particular study is the first presented on ‘functional coffee’ (i.e. coffee with added nutraceuticals).
The Judgement on Java
Clearly, consuming coffee or caffeine can have a myriad of health benefits ranging from the increased mental and physical performance, enhanced lipolysis or fat burning, to an improvement in health (e.g. decreased risk of type 2 diabetes). With the advent of functional coffee (i.e. nutraceuticals added to coffee to enhance its health benefits), the future of java is indeed bright.
Table 1. Caffeine Content in Beverages
| BEVERAGE | SERVING SIZE | CAFFEINE DOSE PER SERVING |
|---|---|---|
| Coffee | 1 cup | 60-150 mg |
| Decaffeinated Coffee | 1 cup | 2-5 mg |
| Starbucks Coffee | 8 ounces | 250 mg |
| JavaFit | 8 ounces | 300-400 mg |
| Starbucks Coffee Latte | 16 ounces | 70 mg |
| Tea (loose or bags) | 1 cup | 20-50 mg |
| Hot Cocoa | 1 cup | 6 mg |
| Cola drinks | 12 oz can | 40 mg |
References:
www.ibiblio.org/herbs/stimulant.html
www.kellymom.com/health/lifestyle/caffeine.html
SIDEBAR – COFFEE – The Newest Functional Beverages
- Coffee drinking does not increase the risk of coronary heart disease or death.1
- Coffee may decrease the risk of oral/pharyngeal and esophageal cancer.2
- Coffee may assist in the prevention of human colorectal cancers.3
- Long-term coffee consumption decreases your risk for type 2 diabetes.4
- Coffee drinking is associated with a reduced risk of alcohol-associated pancreatitis.5
- Coffee may serve as a preventive against liver injury.6
- There is no association between coffee intake or alcohol intake and the risk of pancreatic cancer.7
- Total coffee and total caffeine consumption do not increase the risk of rheumatoid arthritis.8
- Increased coffee consumption was associated with a decreased risk of invasive epithelial ovarian cancer (EOC).9
- Consumption of coffee or caffeine was not associated with breast cancer incidence.10
- Epidemiological studies have found an inverse association between coffee consumption and the risk of certain types of cancers such as colorectal cancers.11
- Several human studies on birth defects have been conducted and the overall results do not implicate coffee as a likely human teratogen. However, there is some evidence that consumption of three or more cups of coffee per day may have a modest effect on lowering infant birth weight. Studies of coffee consumption and increased rates of spontaneous abortion and delayed time to conception are inconsistent and conclusions cannot yet be drawn.12
Sidebar References
1. Kleemola P, Jousilahti P, Pietinen P, Vartiainen E, Tuomilehto J. Coffee consumption and the risk of coronary heart disease and death. Arch Intern Med. Dec 11-25 2000;160(22):3393-3400.
2. Tavani A, Bertuzzi M, Talamini R, et al. Coffee, and tea intake and risk of oral, pharyngeal and esophageal cancer. Oral Oncol. Oct 2003;39(7):695-700.
3. Mori H, Kawabata K, Matsunaga K, et al. Chemopreventive effects of coffee bean and rice constituents on colorectal carcinogenesis. Biofactors. 2000;12(1-4):101-105.
4. Salazar-Martinez E, Willett WC, Ascherio A, et al. Coffee consumption and risk for type 2 diabetes mellitus. Ann Intern Med. Jan 6 2004;140(1):1-8.
5. Morton C, Klatsky AL, Udaltsova N. Smoking, coffee, and pancreatitis. Am J Gastroenterol. Apr 2004;99(4):731-738.
6. Sakamoto W, Nishihira J, Fujie K, Mizuno S, Ozaki M, Yukawa S. Coffee and fitness-coffee suppresses lipopolysaccharide-induced liver injury in rats. J Nutr Sci Vitaminol (Tokyo). Dec 2000;46(6):316-320.
7. Michaud DS, Giovannucci E, Willett WC, Colditz GA, Fuchs CS. Coffee and alcohol consumption and the risk of pancreatic cancer in two prospective United States cohorts. Cancer Epidemiol Biomarkers Prev. May 2001;10(5):429-437.
8. Karlson EW, Mandl LA, Aweh GN, Grodstein F. Coffee consumption and risk of rheumatoid arthritis. Arthritis Rheum. Nov 2003;48(11):3055-3060.
9. Jordan SJ, Purdie DM, Green AC, Webb PM. Coffee, tea and caffeine and risk of epithelial ovarian cancer. Cancer Causes Control. May 2004;15(4):359-365.
10. Michels KB, Holmberg L, Bergkvist L, Wolk A. Coffee, tea, and caffeine consumption and breast cancer incidence in a cohort of Swedish women. Ann Epidemiol. Jan 2002;12(1):21-26.
11. Cavin C, Holzhaeuser D, Scharf G, Constable A, Huber WW, Schilter B. Cafestol and kahweol, two coffee specific diterpenes with anticarcinogenic activity. Food Chem Toxicol. Aug 2002;40(8):1155-1163.
12. Narod SA, De Sanjose S, Victora C. Coffee during pregnancy: a reproductive hazard? Am J Obstet Gynecol. Apr 1991;164(4):1109-1114.
References
1. Salazar-Martinez E, Willett WC, Ascherio A, et al. Coffee consumption and risk for type 2 diabetes mellitus. Ann Intern Med 2004;140:1-8.
2. Smith AP, Clark R, Gallagher J. Breakfast cereal and caffeinated coffee: effects on working memory, attention, mood, and cardiovascular function. Physiol Behav 1999;67:9-17.
3. Costill DL, Dalsky GP, Fink WJ. Effects of caffeine ingestion on metabolism and exercise performance. Med Sci Sports 1978;10:155-8.
4. Conway KJ, Orr R, Stannard SR. Effect of a divided caffeine dose on endurance cycling performance, postexercise urinary caffeine concentration, and plasma paraxanthine. J Appl Physiol 2003;94:1557-62.
5. Bell DG, McLellan TM. Effect of repeated caffeine ingestion on repeated exhaustive exercise endurance. Med Sci Sports Exerc 2003;35:1348-54.
6. Stine MM, O’Connor RJ, Yatko BR, Grunberg NE, Klein LC. Evidence for a relationship between daily caffeine consumption and accuracy of time estimation. Hum Psychopharmacol 2002;17:361-7.
7. Doherty M, Smith PM, Davison RC, Hughes MG. Caffeine is ergogenic after supplementation of oral creatine monohydrate. Med Sci Sports Exerc 2002;34:1785-92.
8. Arciero PJ, Gardner AW, Calles-Escandon J, Benowitz NL, Poehlman ET. Effects of caffeine ingestion on NE kinetics, fat oxidation, and energy expenditure in younger and older men. Am J Physiol 1995;268:E1192-8.
9. Sports Nutrition Review Journal. 1 (1):S1-14, 2004. (www.sportsnutritionsociety.org) poster #16
10. McLellan TM, Bell DG, Kamimori GH. Caffeine improves physical performance during 24 h of active wakefulness. Aviat Space Environ Med 2004;75:666-72.
11. Patat A, Rosenzweig P, Enslen M, et al. Effects of a new slow release formulation of caffeine on EEG, psychomotor and cognitive functions in sleep-deprived subjects. Hum Psychopharmacol 2000;15:153-170.
12. Beaumont M, Batejat D, Pierard C, et al. Slow release caffeine and prolonged (64-h) continuous wakefulness: effects on vigilance and cognitive performance. J Sleep Res 2001;10:265-76.
13. Smith AP, Kendrick AM, Maben AL. Effects of breakfast and caffeine on performance and mood in the late morning and after lunch. Neuropsychobiology 1992;26:198-204.
14. Smith AP, Brockman P, Flynn R, Maben A, Thomas M. Investigation of the effects of coffee on alertness and performance during the day and night. Neuropsychobiology 1993;27:217-23.
15. Battram DS, Shearer J, Robinson D, Graham TE. Caffeine ingestion does not impede the resynthesis of proglycogen and macroglycogen after prolonged exercise and carbohydrate supplementation in humans. J Appl Physiol 2004;96:943-50.
16. Paluska SA. Caffeine and exercise. Curr Sports Med Rep 2003;2:213-9.
17. Motl RW, O’Connor PJ, Dishman RK. Effect of caffeine on perceptions of leg muscle pain during moderate intensity cycling exercise. J Pain 2003;4:316-21.
18. Jacobs I, Pasternak H, Bell DG. Effects of ephedrine, caffeine, and their combination on muscular endurance. Med Sci Sports Exerc 2003;35:987-94.
19. Davis JM, Zhao Z, Stock HS, Mehl KA, Buggy J, Hand GA. Central nervous system effects of caffeine and adenosine on fatigue. Am J Physiol Regul Integr Comp Physiol 2003;284:R399-404.
20. Cox GR, Desbrow B, Montgomery PG, et al. Effect of different protocols of caffeine intake on metabolism and endurance performance. J Appl Physiol 2002;93:990-9.
21. Bell DG, McLellan TM. Exercise endurance 1, 3, and 6 h after caffeine ingestion in caffeine users and nonusers. J Appl Physiol 2002;93:1227-34.
22. Armstrong LE. Caffeine, body fluid-electrolyte balance, and exercise performance. Int J Sport Nutr Exerc Metab 2002;12:189-206.
23. Cole KJ, Costill DL, Starling RD, Goodpaster BH, Trappe SW, Fink WJ. Effect of caffeine ingestion on perception of effort and subsequent work production. Int J Sport Nutr 1996;6:14-23.
24. Spriet LL. Caffeine and performance. Int J Sport Nutr 1995;5 Suppl:S84-99.
25. Graham TE, Spriet LL. Metabolic, catecholamine, and exercise performance responses to various doses of caffeine. J Appl Physiol 1995;78:867-74.
26. Chesley A, Hultman E, Spriet LL. Effects of epinephrine infusion on muscle glycogenolysis during intense aerobic exercise. Am J Physiol 1995;268:E127-34.
27. Van Soeren MH, Sathasivam P, Spriet LL, Graham TE. Caffeine metabolism and epinephrine responses during exercise in users and nonusers. J Appl Physiol 1993;75:805-12.
28. Lindinger MI, Graham TE, Spriet LL. Caffeine attenuates the exercise-induced increase in plasma [K+] in humans. J Appl Physiol 1993;74:1149-55.
29. Spriet LL, MacLean DA, Dyck DJ, Hultman E, Cederblad G, Graham TE. Caffeine ingestion and muscle metabolism during prolonged exercise in humans. Am J Physiol 1992;262:E891-8.
30. Collomp K, Ahmaidi S, Chatard JC, Audran M, Prefaut C. Benefits of caffeine ingestion on sprint performance in trained and untrained swimmers. Eur J Appl Physiol Occup Physiol 1992;64:377-80.
31. Anselme F, Collomp K, Mercier B, Ahmaidi S, Prefaut C. Caffeine increases maximal anaerobic power and blood lactate concentration. Eur J Appl Physiol Occup Physiol 1992;65:188-91.
32. Collomp K, Ahmaidi S, Audran M, Chanal JL, Prefaut C. Effects of caffeine ingestion on performance and anaerobic metabolism during the Wingate Test. Int J Sports Med 1991;12:439-43.
33. Collomp K, Anselme F, Audran M, Gay JP, Chanal JL, Prefaut C. Effects of moderate exercise on the pharmacokinetics of caffeine. Eur J Clin Pharmacol 1991;40:279-82.
34. Ivy JL, Costill DL, Fink WJ, Lower RW. Influence of caffeine and carbohydrate feedings on endurance performance. Med Sci Sports 1979;11:6-11.
- How Coffee Can Help You Attain Fitness and Weight Loss - March 1, 2005